Does PCIe require a special PCIe slot? LIke can you just stick a PCIe card into a normal PCI card solt and expect it to work w/ 100% speed? While you're at it, can you show me a couple of Mobos that have that special PCIe slot if it's required?

PCI Express is a totally different interface from PCI, the bandwidth difference is huge. You will need a board with a nForce4 chipset for PCIe support I believe, I'm not aware of any other chipsets which support it.